There are lots of lists of Apple easter eggs out there, including stuff hidden in the ROMs. (Possibly one of the more famous ones is the hidden boot disk in the Mac Classic, accessed by holding down Command+Option+X+O during startup.)

Massive bump, but I discovered this while digging through the Mac IIvx/IIvi ROM. And it's rather fascinating to see a message like this in an Apple product. This probably wouldn't happen today, but I'm glad it happened at all. This was found in the ROM at 0x4AC8C. I've also edited it for formatting reasons, but is otherwise untouched. Enjoy!

Quote:

Welcome to Brazil.

ROM Software by David Fung with John Cary, Carl Hewitt and Sam Barone.

Special thanks to Mike Puckett, Nick Vaccaro and Eric Anderson.

Tempus Gibbly by Owen Rubin, Giovanni Agnoli, and David Fung.

Cube-E on Brazil aided and abetted by Dean Yu, Chris Derossi, and the Meanies.

That was the era when the easter egg was king -- every hardware and software product had at least one, and many had multiple; generally each team stuck something in.

But towards the mid-90s this phenomenon got a bit out of control such that inventive easter eggs were trumping quality control, and most places put a stop to at least most of it. There were some that were so well hidden that they never got found in QA, but most never made it out of development after that period.

For those not in the know, Brazil was the code name for the Mac IIvx, and Cube-E was the codename for System 7.1.

I like this one (can't remember which ROM it's from):

MacsBug Debugger for Macintosh. Copyright Apple Computer 1982-1986. Originally by Motorola. Adapted to Lisa/Mac by Rich Page 1/25/1982. Enhanced by Steve Capps 11/1/1984. Version IV+ by Ken Krugler 5/13/1985. Disassembler by Ira Reuben 11/21/1986. Version 5.3 by Dan Allen 4/22/1987. This version works w/512KB-4MB of RAM, 64KB,128KB, or 256KB ROMs and with 68000/68020/68030/68851

Interestingly, the IIvx text is the only mention of the Blue Meanies anywhere in the ROMs.

MacsBug Debugger for Macintosh. Copyright Apple Computer 1982-1986. Originally by Motorola. Adapted to Lisa/Mac by Rich Page 1/25/1982. Enhanced by Steve Capps 11/1/1984. Version IV+ by Ken Krugler 5/13/1985. Disassembler by Ira Reuben 11/21/1986. Version 5.3 by Dan Allen 4/22/1987. This version works w/512KB-4MB of RAM, 64KB,128KB, or 256KB ROMs and with 68000/68020/68030/68851

That came from the Mac Classic ROM at 0x67046. But it's also found in the standalone version of MacsBug.